1. Field of the Invention
This invention refers to a leak-free and vibration resistant pipe-flange coupling.
More specifically, this invention refers to a leak-free and vibration resistant pipe-flange coupling, particularly suited to being used in pressurised fluid circuits that are also subject to vibrations, as for example in air conditioners and compressors mounted on vehicles.
In pipe-flange couplings which are required to maintain a stable, leak-free condition in time and withstand vibrations at any frequency, as occurs for example in the compressor circuits of car air conditioners, the present state of the art foresees that the components be welded.
This welding operation, particularly in the case of aluminium, or light alloy cast pipes, involves considerable problems in executing the weld and significant difficulties to ensure that a reliable coupling is achieved.
The main drawbacks are: sagging and burrs on the sealing surface; burning, or porosity in the weld caused by the use of deoxidisers; annealing of the base materials with a weakening of the structural rigidity and the toughness of the materials themselves, etc. In addition, during operation, the inevitable prolonged stress, as a consequence of the vibrations may crack a layer of melted material, breaking the seal.
This invention solves the problem of making the leak-free and vibration resistant coupling between the pipe and flange, without the difficulties and drawbacks of welding and the uncertainties of a screwed coupling.
According to this invention the pipe is inserted inside a hole in the flange and the coupling and the seal between the pipe and flange is ensured by a ring of elastomeric material, compressed and blocked in a groove made on the internal surface of the hole and by heading and expanding the pipe inside the flange hole.